Further comparisons to some denoising methods are also presented.
Firstly, wavelet-based denoising method is adopted to the test signal,
more specifically, a 6-scale undecimated wavelet transform [1]} using Haar wavelet filter.
For denoising, hard-thresholding is applied and the threshold value is chosen by \(3\sigma \) -rule for each subband.
As shown in Figure REF (a), the denoising results adheres the shape of impulse response of the wavelet,
where some of the signal does not have a zero baseline.
